Ultra high density integrated circuit packages

1. A method of forming a thin integrated circuit package, comprising the steps of: (a) providing an integrated circuit package which comprises an integrated circuit element surrounded by a casing, said package having a first and a second major surface, and a perimeter wall defining the package height; and (b) reducing the height of said package by uniformly removing material from one or both of said major surfaces.

2. A method of forming a thin integrated circuit package, comprising the steps of: (a) providing an integrated circuit package which comprises, an integrated circuit element formed on a semiconductor substrate, said integrated circuit element having an upper surface, a lower surface, and a perimeter wall, and a casing which surrounds said integrated circuit element, said casing having an upper surface, a lower surface and a perimeter wall; and (b) uniformly removing material from said lower surface of said casing until said lower surface of said integrated circuit element is exposed.

3. The method of claim 2, further comprising the step of uniformly removing material from said upper surface of said casing.

4. The method of claim 2, further comprising the step of uniformly removing material from said lower surface of said integrated circuit element.

5. The method of claim 4, further comprising the step of uniformly removing material from said upper surface of said casing.

6. A method of forming a thin integrated circuit package, comprising the steps of: (a) providing an integrated circuit package which comprises, an integrated circuit element formed on a semiconductor substrate, said integrated circuit element having an upper surface, a lower surface, and a perimeter wall, and a casing covering said upper surface and said perimeter wall of said integrated circuit element, said casing having an upper surface, and a perimeter wall; and (b) uniformly removing material from said lower surface of said integrated circuit element.

7. The method of claim 6, further comprising the step of uniformly removing material from said upper surface of said casing.

8. A method of forming a modular integrated circuit package, comprising the steps of: (a) providing a plurality of level-one integrated circuit packages each having a plurality of electrical interconnect leads extending therefrom; (b) aligning said level-one packages in a stacked configuration so that said leads from said level-one packages are aligned in an array of columns; (c) mounting a plurality of thermally and electrically conductive rails adjacent to and oriented with said columns; and (d) thermally and electrically coupling said rails to some or all of said leads in said columns.

9. A method of forming a modular integrated circuit package, comprising the steps of: (a) providing a plurality of level-one integrated circuit packages, each including an integrated circuit element formed on a semiconductor substrate, and a lead frame electrically coupled to said integrated circuit element and having a plurality of electrical interconnect leads extending therefrom which provide an electrical path to said integrated circuit element; (b) rendering one or more select leads of the lead frame in each level-one package inactive; (c) aligning said level-one packages in a stacked configuration so that said leads from said level-one packages are aligned in an array of columns; and (d) electrically coupling all of said leads which are aligned in said columns and extend externally from said level-one packages.

10. The method of claim 9, wherein said leads have a section external to said package and a section internal to said package, and wherein said one or more select leads of each package are rendered inactive by disconnecting said external section.

11. The method of claim 9, wherein said leads have a section external to said package and a section internal to said package, and wherein said one or more select leads are rendered inactive by disconnecting said electrical path of said internal section of said select leads.

12. The method of claim 9, wherein said one or more select inactive leads of each level-one package provide a unique address for each package.

13. The method of claim 9, wherein said one or more select inactive leads of each level-one package provide a unique data word bit-position for each package.

14. A method of forming a modular integrated circuit package, comprising the steps of: (a) providing a plurality of level-one integrated circuit packages, each including an integrated circuit element formed on a semiconductor substrate, and a lead frame electrically coupled to said integrated circuit element and having a plurality of electrical interconnect leads extending therefrom which provide an electrical path to said integrated circuit element; (b) rendering one or more select leads of the lead frame in each level-one package inactive; (c) aligning said level-one packages in a stacked configuration so that said leads from said level-one packages are aligned in an array of columns; (d) mounting a plurality of thermally and electrically conductive rails adjacent to and oriented with said columns; and (e) thermally and electrically coupling said rails to some or all of said leads in said columns and external to said level-one packages.

15. The method of claim 14, wherein said leads have a section external to said package and a section internal to said package, and wherein said one or more select leads of each package are rendered inactive by disconnecting said external section.

16. The method of claim 14, wherein said leads have a section external to said package and a section internal to said package, and wherein said one or more select leads are rendered inactive by disconnecting said electrical path of said internal section of said select leads.

17. The method of claim 14, wherein said one or more select inactive leads of each level-one package provide a unique address for each package.

18. The method of claim 14, wherein said one or more select inactive leads of each level-one package provide a unique data word bit-position for each package.